The present invention relates generally to disposable absorbent articles such as training pants, diapers, undergarments and incontinent briefs, and is more particularly related to such pants, diapers, undergarments and briefs which have become known in the art as xe2x80x9cpull-upxe2x80x9d or xe2x80x9cpull-onxe2x80x9d absorbent articles. In one particular aspect, the present invention relates to an absorbent article of the aforementioned types which, due to its unique construction, assures fitness and comfort to the wearer, protects against leakage of fluids and other body exudates and can be readily opened for inspection and removal from the wearer. This invention also relates to ready-to-wear pull-up type absorbent articles.
Disposable absorbent articles such as disposable baby diapers and adult incontinent briefs, underpants, guards and the like articles are widely used in homes and in various health care facilities and institutions. Indeed the use of such articles has become a common sanitary practice, and while initially such absorbent articles were used mostly for infant care, more recently their use has been expanded to include adults as well. In both instances, the absorbent article must be designed to effectively prevent leakage of urine and other fecal materials, while insuring body fit and comfort.
Most presently available absorbent articles are generally unitary in structure, pre-shaped and pre-folded, and comprise an absorbent pad having a liquid permeable top sheet facing the wearer""s body, a liquid impermeable backsheet on the opposite side, and an absorbent sheet or panel disposed between the top sheet and the back sheet. The absorbent article comprises a front side portion, a crotch portion and a backside portion, and further includes elastic members along the circumference of the waist and around the leg openings. While the heretofore commercially available absorbent articles have been somewhat effective against leakage of body fluids and fecal materials, and have therefore met some degree of acceptability, they have not been entirely satisfactory for their intended applications. In other words, they have not proven to be entirely leak proof, nor have they completely prevented issuance of the body exudates outside the diaper or the underpants. These deficiencies are primarily due to inadequate and loose body fit, which result in leakage of the body fluids and solids through the legs"" openings. These problems are even more pronounced in case of adults because of their diverse body shapes and varying contours. Another disadvantage of the commercially available absorbent articles such as diapers, incontinent briefs and the like, is associated with opening and removing the soiled article for inspection without soiling the wearer""s leg or body, or changing the diaper while the wearer has his or her shoes and pants on.
There are several patents which disclose various attempts made in the prior art over the past years to eliminate, or at least minimize, the shortcomings of the present commercially available absorbent briefs. Some of these patents are referred to in the aforementioned commonly assigned, copending application. That application describes a pull-up diaper comprising front and back elasticized waist portions, an insert member having an absorbent core comprising an elasticated crotch region, and at least one elastic member disposed in the longitudinal direction on each side of the crotch region. As shown in FIGS. 1 and 2 of said copending application, the diaper is provided with side seals formed by heat, pressure or combination thereof. In addition, a finite area at each end of the side seals is sealed adhesively or by a hot melt. In an alternative embodiment shown in FIG. 2C of said copending application, male and female Velcro(copyright) regions are provided which are adapted to engage into one another to provide a seal when the front portion of the diaper is folded on the back portion of the diaper.
In a recent patent, i.e., U.S. Pat. No. 6,027,484 issued Feb. 22, 2000 to Anette Remare, a pant diaper is described comprising a piece of fibrous nonwoven or plastic elastic material 9 having two parts 13 and 14 which can be pulled apart to define the side parts or flaps of the diaper. The side parts are fastened together by means of the hooks 15, 16 and the loop 17 as shown in FIGS. 1 and 2. The piece 9 is joined to the outer casing 3 of the front part of the diaper by the glue points 10 which may be homogeneously distributed as shown in FIG. 1 or non-homogenous glue points or fastening means 110 as shown in FIG. 3.
A more recent patent, i.e., U.S. Pat. No. 6,287,287 B1 describes a prefastened disposable article which includes a pair of primary fasteners located on opposed side edges of one waist region. The primary fasteners overlap and releasably engage the opposite waist region. A pair of passive bonds releasably connect the overlapped portion of one waist portion to the opposite waist region in order to maintain the article in prefastened condition.
In general, the briefs and diapers described in the prior art patents have a common structural deficiency in that they are provided with side seams which are welded together by heat and pressure or vibration (ultrasonic welding). Side seals must be sufficiently strong to hold the diaper on the person and must be capable of being torn so that the wearer can tear it easily in order to inspect or change the diaper while having his or her shoes on. Thus, there is a dire need for pull up type absorbent briefs and diapers which are comfortable to wear, highly effective against leakage of fluids and feces, and which can be readily inspected for soil.
Accordingly, it is an object of the present invention to provide a pull-up type disposable absorbent article such as infant diapers, adult incontinent underpants, briefs, guards and the like articles, which overcome the deficiencies and shortcomings of the prior art absorbent articles, including present commercially available garments used for this purpose.
It is another object of this invention to provide disposable absorbent articles which, due to their unique construction, provide improved fit to the body and prevent leakage of urine and other body exudates through the leg openings, and which are easy to take apart for inspection.
It is also an object of this invention to provide such disposable articles which, due to their unique side seals and fastener system, are easy to open up for inspection and which can be readily reassembled after inspection even while the wearer has his or her shoes on.
The foregoing and other objects and features of the present invention will be more fully comprehended and appreciated from the ensuing detailed description and drawing which form parts of this application.
It must be understood throughout this application that the term xe2x80x9cpull-upxe2x80x9d as used herein is synonymous with xe2x80x9cpull-onxe2x80x9d as used in the prior art patents.
The present invention is concerned with providing a ready-to-wear absorbent article such as, for example, a diaper. The diaper comprises a cover sheet, a back sheet, an absorbent layer disposed intermediate the cover sheet and the back sheet, a pair of opposed leg openings and a waist region. The waist region comprises a front waist region and a back waist region connected to each other by a crotch portion, and has belly section which may be elasticated. The front and back waist regions are provided with fasteners for fastening the two regions together. In one embodiment, the fastening system comprises a pair of loop strips in the front waist region, and a pair of correspondingly aligned hook strips in the back waist region such that when the back waist region and front waist region are overlapped, each hook strip releasably engages a correspondingly aligned loop strip. In lieu of a loop strip, the surface of the front waist region itself may act as a loop or a female surface, or a selected segment of the surface may act as the loop for engagement with the hook (male) strip. The front waist region may include a weakened line such as a perforated line adjacent to or in between the strips which can be readily torn in order to inspect the diaper without disengaging the hook and loop fasteners.
In a variation of the invention, the back waist region comprises one or more tabs located at the lateral or side edges of the waist region. Each tab has one surface attached to the back waist region and an opposed hook surface aligned with a loop strip in the front waist region. In order to fasten the diaper, the back waist region and front waist region are overlapped so as to engage the hook surface of each tab with a correspondingly aligned loop surface.